The films of the present invention are particularly adapted and useful in bags used for liner applications. Bag liners may be used to collect waste at restaurants, hotels or business locations. Some of the properties desired of these films are as follows: puncture resistance, tear resistance and tensile strength in the transverse and machine directions, high gloss, end use impact resistance, the ability to produce the film in thin gauges, low specific gravity and thus high yield in area per pound, tensile toughness, and high modulus of elasticity.
Of particular importance in the present application are improved dart drop, total energy dart drop and gloss. Improved dart drop and total energy dart drop are desirable because liners preferably should remain intact to prevent items such as waste from protruding out of the liner. Gloss is desirable because it provides a surface which is attractive and aesthetically pleasing to consumers.
A particular film is selected for an end use because of the particular properties it possesses. A film may have some properties which are desirable and others which are less so. For example, while a pure high molecular weight high density polyethylene (HMW HDPE) film has superior strength, toughness and puncture resistance, it has significant shortcomings with respect to gloss and dart drop values. Another film, metallocene-catalyzed polyethylene, while having superior gloss, has only moderate tensile strength and significant cost limitations.
A need, therefore, exists for films which have excellent impact and overall toughness as well as superior gloss without compromising key structural characteristics.